Conventional double-hung windows are mounted in a window frame which is attached to the structural framing of the surrounding wall. The window frame generally comprises a pair of horizontally spaced-apart vertical jambs having a jambliner mounted thereon which faces the window opening. Each of the jambliners includes a pair of horizontally spaced-apart and vertically disposed channels in which mechanical balances are positioned. Each sash of the conventional double-hung windows is provided with cam pivots extending laterally therefrom adjacent the lower ends thereof for connection to locking terminals associated with the mechanical balances. When the upper end of one of the sashes is tilted inwardly to facilitate the removal of the sash from the window frame, the cam pivots on the sash to permit the knife lock portion of the locking terminal to engage one wall of the associated channel so that the locking terminal will remain in place, under tension, in its respective channel during the time that the window is removed from the frame.
A problem arises in the full tilt, double-hung windows during the shipment thereof from the factory to the point of sale or use. During shipment, the jambs may bow outwardly with respect to the sashes which may cause one or more of the cam pivots which then causes the locking terminal to quickly move towards its mechanical balance. The movement of the locking terminal towards its mechanical balance is a snap-like action which may cause damage to the locking terminal or the mechanical balance itself. Further, once the window is ready for installation, the sashes must be removed and the locking terminals attempted to be repositioned in their proper position to facilitate the engagement of the cam pivots on the sashes with the locking terminals.
Further, when the full tilt, double-hung windows are subjected to wind-loading tests, the force of the wind may also cause the jambliners to deflect which also causes disengagement of the cam pivots from the locking terminals.
It is therefore a principal object of the invention to provide an improved cam pivot for a full tilt, double-hung window.
Yet another object of the invention is to provide a cam pivot for a full tilt, double-hung window which includes means for preventing the disengagement thereof with the locking terminal during shipment of the window or during wind loading of the same.
Still another object of the invention is to provide an improved cam pivot for a full tilt, double-hung window which includes a locking lug which is received between the walls of a channel on the locking terminal to prevent the separation of the same during shipment or wind loading.
These and other objects will be apparent to those skilled in the art.